Find the contiguous subarray within an array (containing at least one number) which has the largest product.
For example, given the array [2,3,-2,4],
the contiguous subarray [2,3] has the largest product = 6.
神马复杂度为n^2,n^3的解法肯定是会超时的,ok目标为O(n);
LeetCode : Maximum Product Subarray
原文：http://www.cnblogs.com/64open/p/4114393.html